Looks as commit not backported
https://github.com/kamailio/kamailio/commits/5.5/src/modules/mohqueue

On Thu, Jun 10, 2021 at 9:09 AM RDB Programmer <rdbprog@gmail.com> wrote:
Daniel,

Will this release include the latest changes to mohqueue that I pushed to the master on May 19?

Bob 
From: Daniel-Constantin Mierla <miconda@gmail.com>
Date: Wed, Jun 9, 2021 at 6:00 AM
Subject: [SR-Users] Releasing Kamailio v5.5.1
To: Kamailio (SER) - Devel Mailing List <sr-dev@lists.kamailio.org>, Kamailio (SER) - Users Mailing List <sr-users@lists.kamailio.org>


Hello,

I am considering to release Kamailio v5.5.1 sometime next week, likely
on Tuesday or Wednesday (June 15 or 16, 2021). This is the usual heads up
notification to see if anyone is aware of issues not yet reported to bug
tracker and if yes, do it as soon as possible to give them a chance to
be fixed.

Cheers,
Daniel

--
Daniel-Constantin Mierla -- www.asipto.com
www.twitter.com/miconda -- www.linkedin.com/in/miconda



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